For each individual petal, we've constructed a separate "flow" line, as covered in the leaf construction exercise. While these are petals, and not leaves, the same principle applies because both are relatively flat and as such are heavily impacted by the flow of wind and air currents that surround them. You'd apply the same tactic to any such object or form.
Make sure you're drawing each flowing line with confidence and with consideration for how those forces are going to be pushing on your leaf. Don't draw shallow, stiff lines - take your time, apply the ghosting method, and don't half-ass it. The flow line is the core that defines the behaviour of each leaf or petal.